SARS-CoV-2 semi-quantitative total antibody correlates with symptoms of long COVID in both vaccinated and unvaccinated subjects

Abstract

Long coronavirus disease (COVID) is defined as an infection-associated chronic condition that occurs after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and is present for at least 3 months as a continuous, relapsing, and remitting, or progressive disease state. While COVID-19 vaccines have been credited by public health officials with preventing COVID-associated morbidity and mortality, a portion of the population reports post-vaccination syndrome, often concerning long COVID. To investigate the association between post-vaccination syndrome and long COVID, we performed an observational cohort study at our outpatient clinical practice, evaluating SARS-CoV-2 semi-quantitative spike Ab in 100 consecutive patients (47% female and 53% male) with symptoms of long COVID. A total of 81 participants (46.9% female and 53.1% male) with post-vaccination syndrome and 19 unvaccinated participants (47.4% female and 52.6% male) with symptoms of long COVID were evaluated. SARS-CoV-2 Semi-Quant Spike Ab in the vaccinated cohort showed an average result of 11356.86 U/mL, whereas SARS-CoV-2 Semi-Quant Spike Ab in the unvaccinated cohort showed an average result of 1631.94 U/mL. The findings reveal potential immune differences in both individuals with long COVID and those with post-vaccination syndrome that merit further investigation to better understand these conditions and inform future research into diagnostic and therapeutic approaches.

Keywords

COVID-19 / Spike / SARS-CoV-2 / Long COVID

Acknowledgments

None.

Funding

None.

Conflict of interest

The authors declare no conflict of interest.

Author contributions

Conceptualization: Henry P. Barham

Investigation: James R. White, Henry P. Barham

Methodology: James R. White, Henry P. Barham

Writing-original draft: James R. White, Henry P. Barham

Writing-review & editing: All authors

Ethics approval and consent to participate

Consent was obtained from the participants before their participation.

Consent for publication

Participants gave consent for publication of their data in this study.

Availability of data

Data are available from the corresponding author upon reasonable request.

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